1. Field of the Invention
The present invention relates to an integrated gasification combined cycle system provided with a carbon dioxide separation and recovery device and, in particular, to a gasification power generation system provided with a carbon dioxide separation and recovery device in which carbon dioxide contained in exhaust gas discharged from a gas turbine is recovered in the carbon dioxide separation and recovery device, and shift reaction heat generated by a shift reaction to convert carbon monoxide into carbon dioxide is effectively recovered in a shift reactor of the carbon dioxide separation and recovery device in an integrated gasification combined cycle system which generates power by burning gasified fuel gas containing carbon monoxide and hydrogen in a gas turbine.
2. Description of Related Art
There have been techniques to gasify coal and biomass to be used as fuel for gas turbines. In the case of coal gasification, in particular, the representative components of the gas produced are carbon monoxide (55% by volume), hydrogen (20%), nitrogen (20%), carbon dioxide (3%), steam (2%), and others, although they may vary depending on the type of coal.
Therefore, the shift reaction to obtain carbon dioxide and hydrogen from carbon monoxide and steam, the main components of gas produced in coal gasification, represented by the following equation (1) is generally used in carbon dioxide recovery systems at chemical plants, etc.CO+H2O→CO2+H2  (1)
More specifically, a shift reaction represented by the equation (1) above is caused in a shift reactor, gasified coal is converted into hydrogen and carbon dioxide, then the hydrogen is used as fuel gas for a gas turbine, and the carbon dioxide is absorbed by an absorption liquid at a carbon dioxide absorption tower. This shift reaction is an exothermic reaction.
Japanese Patent Laid-open No. 2008-108621 discloses a technique concerning a fuel cell power generation system provided with a carbon dioxide recovery device having a shift reactor in which a shift reaction converts carbon monoxide into carbon dioxide.    Patent Document 1: Japanese Patent Laid-open No. 2008-108621